Description: Define a function generating sets of integers using ahalf-open range.
Read ( M ..^ N ) as the integers from M up to, but not
including, N ; contrast with ( M ... N )df-fz , which
includes N . Not including the endpoint simplifies a number of
formulas related to cardinality and splitting; contrast fzosplit with
fzsplit , for instance. (Contributed by Stefan O'Rear, 14-Aug-2015)